Automatic fluid pressure control system



July 5, 1949. H. B. HOLTHOUSE, SR, ET AL 3 AUTOMATIC FLUID 'PRESSURE CONTROL SYSTEM v Filed Oct; so, 194 4 Shee'ts-Shee t 1 2 I m Q kmma u Y v h g EMINVENTORS o q HARRYBHOLTHOUSESR.

N mrmvangfgrwussm.

,HOLTHOUSE JR- mxm l v4, Sheets-Sheet 2 y B. HOLTH U 55. 5R;

HARR HARR W WEE 3E H B HOLTHOUSE, SR, ETAL AUTOMATIC FLUID'PRESSURE CONTROQ SYS TEM July 5, 1949.

Filed Oct. 30, 1944 Patented July 5, 1949 AUTOMATIC FLUID PRESSURE CONTROL SYSTEM Harry B. Holthouse, Sr., and HarryB.

Holthouse,

.Jr.-, Ghicago, Ill. Application October 30, 1944, Serial No. 561,136

(01 Bil -97) 3 Claims.

This-invention relatesgenerally tocontrol systerns and in particular to an automatic fluid pressure controlsystezn for clothes-washing machines, dish-washing machines or any machine wherein a cycle of operations is performed to effeet a desired actioii on the material handled by themachine. i

Control systems for machines of this type to automatically accomplish a cycle of sequential predetermined-operations are well known and are usually of an electrical nature including actuatins solenoids controlled with suitable switch devices. These systems are generally complicated and bulky and relatively expensive so as to appreciably increase the over-all cost of the machine tdwhich they are applied. A further objection to devices of this kind is found inthe fact that they are not com letely flexible in adjustment or setting to provide for the ready performance of any one of a series of operations, within a predetermined cycle of operations, without generally being put out of adjustment to later provide iorth-e proper performance of the cycle of operations. Yet another objection toelectrical control systems in washing machines is in the danger of possible-shocks to the machine operator, and the high cost of maintenance service on theelectr'ical equipment due to dampness and corrosion.-

It is an object or this invention, therefore, to provide an improved fluid pressure control sys tern;

A further object of this invention is to provide an automatic hydraulic control system for a clothes-washing machine in which water at or below lcity' main pressure is selectively applied to actuating devices for the operating units of the machine.

Another object of this invention is to provide an automatic hydrai'ilic control system for a clothes-washing machine which can be operated with water pressures as low as five pounds per square inch.

Another object of this invention is to provide automatic hydrauliccontrcl system which is capable of being quicklyadjusted or set to provide for the performance oi. any one operation or aseries of operations, within a cycle of operations, without eifecting, a. performance of the remaining operations in suclr cycle.

A still further object ofthis invention is to provide an automaticuhydraulic control systemior a clothes-washing machine: and the" like which is relatively inexpensive in cost, comprised of parts which are of a like construction, compact ing pressure actuated in assembly, and capable of operating efliciently over long periods of time with a minimum of attention and adjustment.

A still further object of this invention is to provide an automatic hydraulic control system for a clothes-washing machine in which the time required for the washing period can be varied between wide limitswithin a predetermined angular distance of rotation of a rotatable pro-selector unit.

Yet another object of this invention is to provide an automatic hydraulic control system for a clothes-washing machine in which the pressure of the water supplied to the washing tub is so- 1 lectively applied to actuate operating units in the machine in a pre-determined manner to effact a complete washing and drying action.

Yet another object. of this invention is to provide an automatic fluid control system for a clothes-washing machine in which a control head may be located remotely from the operating units to be controlled.

A feature of this invention is found in the provision of an automatic hydraulic control systern for a clothes-washing machine in which an electric operating motor for the machine is used as a timing means for a pro-selector unit adapted to selectively operate valve means in a fluid pressure system to control the application of the fluid pressure on pressure actuated devices for the operating units in the machine. v A further feature of this invention is found in the provision of an automatic hydraulic control system including a fluid pressure system havdevices, and a city main pressure supply, with the to provide for the draining of any accumulated moisas a source of fluid fluid system arranged by gravity therefrom ture.

Yet another feature of this invention is found in the provision of a control washing machine having an operating motor, in which each operating unit in the machine is operatively associated with a fluid pressure actuating device connected with a source of fluid pressure such that the load to be carried by an operating unit is gradually applied on the motor to appreciably reduce any sudden overloading of the motor.

A still further feature of this invention is found in the provision of a fluid pressure control system in which the fluid pressure to be applied on an actuating device for an operating unit is controlled by means adapted to selectively squeeze closed a flexible conduit connectingkthe system for a clothes-v 3 actuating device with a source of fluid pressure.

Further objects, features and advantages of this invention will become apparent from the following description when taken in connection with the accompanying drawings in which:

Fig. 1 illustrates schematically the hydraulic control system of this invention as applied to a clothes-washing machine;

Fig. 2 is a sectional view of the control head of the control system as seen along the line 2-2 in Fig. 1;

Fig. 3 is a sectional View taken along the line 3-3 in Fig. 1 showing the drive connection of the washing machine operating motor with a power transmission mechanism for the machine clothes receptacle;

Fig. 4 is an elevational view of the control head looking toward the right in Fig. 1;

Fig. 5 is a sectional view through a control valve which forms part of the control head, as seen along the line 5-5 in Fig. 1 with certain parts broken away to more clearly show the valve construction;

Fig. 5a is a perspective View of a rocker arm used in the valve shown in Fig. 5;

Fig. 6 is an enlarged sectional view taken on the line 6-6 in Fig. 1 showing a switch device, and actuating cam therefor, for the operating motor of the washing machine;

Fig. '7 is an enlarged detail sectional view of a control valve and actuating device therefor one of which is used for controlling the supply to, and another the draining of water from the washing machine tub;

Figs. 8 and 9 are illustrated substantially similarly to Fig. 5 and show the control valve in changed positions;

Fig. 10 illustrates schematically the relative arrangement and shape of the cams for operating the control valves in the control head;

Fig. 11 illustrates diagrammatically one of the time cycles available for the various clotheswashing and drying operations as controlled by the control system of this invention;

Fig. 12 illustrates a modified form of the control valve shown in Fig. 5;

Fig. 13 is a sectional view on the line I3Il3 in Fig. 12;

Fig. 14 is a plan view of a modified form of control head;

Fig. 15 is a sectional view of the modified control head taken on the line [5-45 in Fi 14;

Fig. 16 is a fragmentary sectional view as seen along the line l6l6 in Fig. 15; and

Fig. 17 is a perspective view of the device for varying the clothes-washing period in the control head shown in Fig. 14.

The control system of this invention is illustrated in the drawings as applied to a clotheswashing machine having a rotatably supported clothes receptacle, which is oscillated during a clothes-washing operation and rotated at a relatively high speed during a clothes drying or water extracting operation. A tub surrounding the clothes receptacle is provided with a usual water inlet adapted to be connected to the supply line from a city main, and an outlet for draining water from the tub.

Both the tub inlet and tub outlet are provided with valves to control the supply and draining of water from the tub. A transmission mechanism is operatively associated with a pair of friction clutches selectively actuated to provide for either an oscillation or rotation of the clothes receptacle, with the transmission mechanism be- 4 ing connected with an electrical operating motor. The motor is also clutch-connectible with a centrifugal type pump which functions to produce the washing action within the clothes receptacle.

The control system for operating the above described operating units of the washing machine is of fluid pressure type and includes a control head, which may be located remotely from the washing machine, having a rotatable pre-selector unit operated in a timed relation by the operating motor for the Washing machine. The control head includes a fluid pressure chamber or header connected with a usual city water main so that the fluid within the chamber is at a pressure maintained by the pressure of the water in the city main. The inlet and outlet valves for the wash tub, the clutch devices for connecting the motor driving shaft with the clothes receptacle power transmission mechanism, and the centrifugal pump, are each individually and operatively associated with a corresponding bellows unit. Each bellows unit in turn is individually connected through a conduit means with the fluid chamber in the control head.

Mounted in the control head is a series of valves corresponding in number to the conduit means for the bellows unit, and adapted to control the application of the fluid pressure from the fluid chamber to the bellows units. Each valve in the control head has an actuating rocker member. The pro-selector unit includes a cam shaft having cams mounted thereon corresponding in number to the actuating members for the valves. The operating motor for the washing machine is connected with the pre-selector unit such that the cam shaft is rotated through one revolution in the period of time required to perform a complete washing, rinsing, and waterextracting action on the clothes. The power for actuating the operating units in the washing machine is thus provided entirely by the utilization of the available water pressure in a usual city main, with the operating motor for the washing machine being used in the control system only as a source of power for operating the preselector unit in a timed relation.

Referring to the drawings the control system of this invention is shown in Figs. 1 and 3 as applied to a washing machine having a tub 20 and a clothes receptacle 2| formedwith a perforated bottom and side walls. The receptacle 2! is mounted on an upright shaft 22 rotatably supported in a gear housing 23. Mounted on the shaft 22 within the gear housing 23 are a pair of axially spaced bevel gears 24 and 26 which are in meshing engagement with bevel gears 21 and 28 mounted on shafts 29 and 3|, respectively. The shaft 29 is connected through a clutch device 32 to a shaft 33 which carries pulleys 34 and 36. The pulley 34 is connected through a belt 31 with a pulley 38 mounted on a shaft 39 of an electrical motor 4|.

The shaft 3| is connected through a clutch device 42 with a shaft 43 having a rocker arm 44 mounted on its end 46. The free end of the rocker arm 44 is pivotally connected-to one end of a link 41, the opposite end of which is rotatably supported on a crank arm 48 mounted at one end of a shaft 49. A pulley 5| is carried at the opposite end of the shaft 49 and connected through a belt 52 with the pulley 36 on the shaft 33. The shafts 33 and 43 are indicated in Figs. 1 and 3 as being rotatably supported in journal members 45 carried on a frame portion 5a of the washing machine. Shaft 49 is rota-..

tably supported in a bearing also mounted on. the frame portion 50.

In the operation of the motor 4| a rotary move. ment is imparted to the shaft 2 and. in turn t the clothes recep acle 31. on connection of the. shafts Z9. and 33 through the clutch device 32. To oscillate the clothes receptacle 2| the shafts 29 and are disconnected and the shafts 3| and 43 connected through the clutch device 42. It is. to be understood, of course, thatthe action of the clutch devices 32 and 42 is alternate, that is one clutch device is in an open position when the oth er clutch is a closed position.

i The oscillation of the clothes receptacle 2| takes place during the clothes-Washing and rinsing operations. During these operations i the clothes are agitated by water discharged from the outlet 53 of a centrifugal pump 54 having a shaft 90a connected with theshaft 39 of the motor 4| through a clutch device 55 (Fig. 1). The water from the pump outlet 53 is ejected into the clothes receptacle 2| through a series of slots 51 having an angular length which is equal substantially to the oscillatory travel of the clothes receptacle. The pump inlet 58 is connected to the bottom of the tub '20 so that the pump 54 functions to circulate the water through the tub 20 in a closed system. Water is supplied into the tub 29 through an inlet 59 having a control valve 6|], with the inlet 6| to the control valve 60 being adapted for connectionwith a source *of Water supply for the washingmachine, such as the usual city water main. An outlet 62 for draining water from the tub 20 is connected to the bottom of the tub and is provided with a control valve 63. Thevalves 60 and 63 for the tub inlet 59 and outlet 62, respectively, are of a like construction so that only the control valve 60 will be described in detail.

With reference to Fig. 7 the valve 60 is seen to include a casingll) having a valve seat 64 therein with an orifice or opening 66 for communicating thevalve inlet 6| with the tub inlet 59, A fluid pressure responsive actuating device located within the casing 10 iscomprised of an expandible and contractible bellows unit 61 which is secured at its end 68 to the valve casing. The opposite end of the bellows 61 has an outwardly projected valve stem 69 extended through the orifice 66 and carrying a valve member 1| adapted for seating engagement with the seat 64. A spring mounted on the valve stem 69 is arranged in compression between the valve member H and the valve casing 10 and normally retains the valve member H in seatingengagement with the valve seat 64. Opening of the valve member II is accomplished by the bellows 81 in a manner which will be later explained.

. The clutch devices, 32, 42 and 56 are of a like construction and similarly actuated by an associated fluid pressure responsive device so that only the clutch device56 will be referred to in detail (Fig. 1). The clutch 56, which connects the pump 54 with the motor 4|, includes a friction disc 12 mounted on the motor shaft 39 and aseoond friction disc 13 rotatable with the pump shaft 60a, but axially movable on the pump shaft for movement into and out of frictional engagement with the disc member 12. Disc members 12 and '13 are normally held in a frictionally engaged position, to connect the shafts 39 and 60a, by a coil spring 14 mounted about the pumpshaft 60a and arranged in compressionbetween a hub 82 for the disc member 13 and the housing of pump 54. Thediscomember 13 is moved out of frictionalengagement with the disc member 12,110

cl sconnect the shafts as and 60a by a bellows uni 16 secured at one end to a bracket 1! which i supported on the pump. housing. Thecther nd of he bellows unit; 16 has an outwardlyproa iecting pin is pivoted to one end of a-lever arm ldwhich in. turn is pivoted at 8| on the frame portion 50. The opposite/end of the lever arm- 19 is of yoke shape receivable in an annular groove. formed in a hub 82 for the disc/member lit. It is seen, therefore, that on expansion of he bellows unit 16, thedisc. member 13 is moved out oi an engagingposition with thedisc member 12 bythe lever. arm 19 acting against thepressure of the spring 14.

The. disc members 12a and 13a of the clutch device 32fo-r connecting the shafts 29 and 33 to impart a'rotary movement to the clothes receptacle 2! are normally held outoffrictional en.- ga ementby a tensionspring 83 connected atone end to. a pivoted lever arm 19a and at its opposite end to the gear casing: 23. The lever arm 1.9a pivoted on the frame portion 50 and is pivotally attached at one end 89 to the movable end of a. bellows unit. 84, the opposite end of which is 1 mounted on a bracket 86 secured to the frame por tion 50. End ado-f the lever arm 19a is of a yoke shape adapted to ride in an annular groove formed in ahub so for thedisc member 13a.

The, clutch device 4 2 for connecting the shafts 3| and 423 to oscillate the clothes receptacle 21" normally has its disc members 121) and 13b in a frictionally engaged position, which is retained bya coil spring 81 mounted about the shaft 43 and arranged in compression between a stop member 88 on the shaft 43 and the hub of the disc. member rec. A pivoted lever arm 19b has its:

yoke end receivable in an annulargroove formed in: the hub 95 of the disc member 13b and its other end pivoted to-themovable end of a bellows unit 89, the opposite end of which is attached to a bracket 9| mounted on the frame portion 510.. The lever arm 19b is pivotally supported at Hill on the frame 5 9.

All of the bellows units 61 1-6, 84 and 89 are of a like construction and expansible and contractible in response toa fluidoperate associated actuating unit, in a manner which will now be described.

- A selective application of a fluid pressure to, the bellows units to provide a pre-determined' cycle of washing, rinsing and drying operations on the clothes in the receptacle 2| is accomplished by means including a pro-selector unit." 912 formed as part of a control head, indicated generally at 93 in Fig. 1, and; which control head may be located adjacent to or" remotely from the washing machine mechanism.

, The control head 93 comprises a fluid pressure.

header 94 and a waste or drain header 9,6 oppositely arranged on a base member I95 in a. spaced relation between end frame members i 9.]: and 98 (Figs. 1 and'4). Fluid is supplied to the header 94-under pressure through an inlet pipe; 99 connected to any-- suitable continuous source of pressure supply such as the usual city water main. It is apparent, therefore, that the fluid in. the header 94 is continuously maintained. under pressure. The pipe 99 has apressure regulating valve 100w and a valve Ill! for controlling" the. pressure and supply of fluid to the header 94. The waste header 9B isprovided with a drain pipe. I23.

The header 94 1s provided with aplurality of? longitudinally spaced outlets I02 (Figs. 4 and 5) 15 oppositely arranged trom corresponding inlets pressure therein to" I03 to the waste header 96. Each outlet I 02 from the pressure header 94 is connected with a corresponding inlet I03 to the waste header 96 by a flexible tube connection I04 composed of rubber ora like material. Projected through the base member I95 in a longitudinally spaced relation are the ends IIO of conduits I05, I06, I01 and I 08 corresponding in number to the flexible tubes I04, with the ends IIO bein connected with an associated tube I04 in a substantially T connection, as illustrated for the end IIO of the conduit I08 in Fig. 5. The opposite ends of the conduits I05 and I06 are fluid connected with the bellows B1 in the valves 60 and 63, respectively, while the opposite ends of the conduits I01 and I08 are fluid connected with the bellows 84 and 89 for the clutch devices 32 and 42, respectively (Fig. 1).

The conduit I09 is connected at one end to the bellows 16 for the clutch device 56, and at its opposite end to the conduit I08 to provide for a concurrent actuation of the bellows 16 and 89 as will be later explained. The application of a fluid pressure from the header 94 to the conduits I05, I05, I01 and I08I09 is controlled by valve units I05e, I050, I010 and IBM, respectively, each of which valve units includes a tube connection I 04. Since each of the valve units I05e-I080 is of a like construction, only the valve unit I080. will be described in detail.

Referring to Figs. 4 and 5 the valve unit I08a is shown as including a, pair of rocker arms I081) and I080 mounted on a rock shaft II3 supported in the end frame members 91 and 98 in a parallel relation with the headers 94 and 98 and in alignment with, but spaced from, the projected ends I I of the conduits I-I08, inclusive. The rocker arms I081) and I080 are of a like construction and only the arm I081), therefore, will be described in detail.

As shown in Fig. 5a the rocker arm I081) is integrally formed at one end with a transversely extended cylindrical portion I I4 of a length somewhat greater than the diameter of the tube connection I04. A pin I I6 is projected laterally from one side of the rocker arm I08b at the opposite end thereof and constitutes a follower for a cam I08d mounted on a shaft II1, which is supported for axial and rotatable movement in the end members 91 and 98 and arranged in a parallel relation with the shaft II3.

In the assembly of the valve I08a the rocker arms I081) and I080 are reversely positioned adjacent each other on the shaft H3 so that their cylindrical end portions II4 are arranged at opposite sides of the shaft H3 and in turn to opposite sides of theprojected end IIO of the conduit I08. Further, as best appears from Fig. 4, the followers IIB are extended in opposite directions for operative association with their respective cams I08d and I08e.

As shown in Figs. 1 and 4 the associated pairs of rocker arms I051) and I050, I061) and I060, I011) and I010, and I081) and I080 for the valve units I05e-I080, inclusive, are longitudinally spaced in a stacked relation on the shaft II 3, Likewise the cams IBM and I08d, and I05e and I080, inclusive, are arranged in pairs in a stacked arrangement longitudinally of the shaft I I 1.

With reference to Fig. 10 it is seen that each associated pair of cams I05d and I05e through I08d and I08e, inclusive, are of a like construction except that the high spots on the. cams sociated cams I05d-I08d, inclusive. In the assembly of each pair of cams on the shaft II3 the cams I05e-I082, inclusive are arranged so that their high spots overlap the high spots on their respective associated cams I05d-I08d, inclusive. on rotation of the shaft H3 in the direction of the arrows shown in Fig. 10, the rocker arms I05e-I080, inclusive, are operated ahead of their corresponding rocker arms I05e-I081), inclusive, for a purpose which will become apparent in the following description of the operation of the valve unit I08a.

In the operation of the valve unit I080, the rocker arms I081) and I08c are normally held in a stopped position against a stop bar I I8, supported in the end frame members 91 and 98 in a parallel relation with the shafts H3 and H1 by springs '9 connected at one end to a rocker arm I081) and I080, and at their opposite ends to a bracket I2I carried on the pressure header 94 (Fig. 5). In this position the end portion I I4 of the rocker arm I081) is pressed against the tube connection I04 so as to squeeze closed that portion of the tube I04 between the conduit end H0 and an outlet I02 for the pressure header 94. To assure a positive squeezing closed of the tube I04 there is provided on the base I95 a fiat spring I22 at a position opposite from the zone of engagement of the tube I04 with the end II4 of the rocker arm I081). The tube I04 is thus pinched between the rocker arm i081) and. the spring I22, soas to shut off the supply of fluid from the pressure header 94 to the conduit I08.

The rocker arm I080 in its normal rest position against the stop rod II8 has the end portion II4 thereof in contact engagement only with the tube I04 so that the conduit I08 is open to the waste header 9B. Arrangedat the opposite side Ovf the tube I04 from the end II4 of the rocker arm I080 is a second spring I24 which cooperates with the rocker arm I08:c in all respects similar to the cooperative action between the rocker arm I081) and the spring I22.

On rotation of the shaft II 1 in a counterclockwise direction, as viewed in Fig. 6, the high spot I 6| on the cam I080 initially engages the rocker arm I08c to pinch or squeeze-close the tube connection I04 between the conduit end 0 and the waste header96, as shown in Fig. 8. As a result the conduit I08 is initially closed from communication with both the pressure header 94 and the waste header 95. On a continued rotation of the shaft II1 the 10am I08e continues to hold the rocker arm I080 in a tube-closing position concurrently with the action of the cam I08d to move the rocker arm I081) against the pressure of its associated spring I I 9 to an opening position for the tube I04, as shown in Fig. 9. The conduit I08 is thus closed by the squeezing of the tube I04 by the rocker arm I081), from communicating with the inlet I03 to the waste header 96, and open to the outlet I02 of the pressure header 94. This relative position of the rocker arms I08?) and I080 is retained for a predetermined period of time, depending upon the angular length of the high spot I59 on the cam I08d and the speed of rotation of the shaft II1, which period is suiflcient to provide for a predetermined actuation of the bellows 16 and 09 which are connected With the conduit I08.

To release the fluid pressure in the conduit I08 the cam I08d initially provides for the return of I03 tothe waste header 96 so that there is no unnecessary waste of thefluid from the pressure header 94. In other wordsthe fluid from the pressure header 94 is initially introduced into the conduit I08, and then released from the conduit I II8 into the waste header 96, without at any time passing directlyfrom theoutlet I02 of the pressure header 94into the inlet I03 of the waste header. This is accomplished by virtue of the factthatalthoughthe cams I Il5dIII8d are of substantially the same shape as their corresponding cams IU5eIIl8e,fthe high spots on the cams I 95e-III8e are of a greater angular length than the high spots on their corresponding cams I05dI08d. As a result in the operation of a valve unit, such as 108a, the closing and opening of the tube I04loy therocker arm IOBfc overlaps the opening and closing. of the tube I04 by the rocker arm I08b,

The valve units ID5d-IIJ8a, inclusive, are selectively operated by the pre-selector unit 92 which includes the cams IIl5d-III8d, and I fl5e-I08e, both inclusive, and" the cam shaft 1, which extends through the end frame member 91 and into a gear housing I23 attached to a reduced section 90a of the base member I95 (Figs. 1 and 4) The cam shaft I I1 is. driven by the motor 4| which constitutes a timing means for the pre-selector unit 92. Connection of the cam shaft II1 with the motor 4| is made through a gear train located in the gear housing I26 and including a worm gear I28 mounted on a flexible shaft I25 and operatively associated with a worm wheel I21 which is mounted on a shaftI3I. rotatably supported at one end in a casing I 321 for the gears I21 and I28 and at its opposite end in a bearing I33 formed on the gear housing I26 (Figs. 1 and 2). The flexible shaft I25is connected with the motor shaft 39 through a coupling I33.

A gear I34 mounted on the shaft I3I is connected through gears I 36 and I31 with a gear I38 rotatably supported on the cam shaft H1. The gear I38 has a serrated hub adapted for interlocking engagement withfla serrated collar I39 fixed on the cam shaft IIT within the gear housing I 26. The serrated collar I39 is normally held in, looking position with the serrated hub of gear I38 by a coilspring I 4| positioned about the cam shaft III and arranged in compression between the collar I39 and a side wall of the housing I26 so as to normally bias the shaft II1 downwardly as viewed in Fig. 1.

The cam shaft 111 is projected through the gear housing I26 and at its projected end carries a manual control knob I42 and an indicating pointer I43 which arekeyed on the shaft II1. By, manually gripping the control knob I42 the shaft II1 is axially movable upwardly, as also viewed in Fig. 1 against the pressure of the spring I 41 a distance suflicient to disengage the serrated collar I39 from the hub of gear I38. With the shaft I11 manually held in such axially moved position the cam shaft III is manually rotatable independently of .the will appear later.

Operation of themotor H to drive the cam shaft II! is controlled bya switch device I45 (Figs. 1 and 6) including a pivoted actuating lever I46 having a follower I'41 opcratively associated with a cam I43mounted on the cam shaft H1. The lever. I46 is pivoted on a shaft I49 mounted in the switch housing I M and biased gear I 38 for a purpose which by a spring I 52 so that the cam follower I41: is in following engagement with, the cam. I48. the follower I41 is on the hlghsp'ot I53 of the l0 cam I48 switch contacts I54 and I56 are opened to in turn open an electrical circuit (not shown) for the motor 4| and including conductors I51. With the follower I41 off of the high spot I53 the contacts I54 and I56 are closed by the action of the spring I52 to close the circuit for the motor 4 I.

The control system is readily applicable to provide for the performance of any number of operations within a predetermined cycle of operations by merely varying the number of valve units in' the control head 93 to correspond to the number of operating units in the machine to be controlled. It is understood, of course, that the number of pairs of cams in the preselector unit 92 will always correspond to the number of valve units in the control head 93. Thus although only four valve units I II5a -I 08a, inclusive, are illus-- trated in Fig. 1, as included in the control head 93, this number is only shown by way of example of the application of the control system to a washing machine having the number of operating units illustrated in the drawings.

Let it be assumed that the cycle of operations to be performed corresponds to the operations indicated on the dial I58in Fig. 14 which is similar in all respects to the dial I58 shown in Fig. 1 on the gear casing I 26 for the pointer I43. From aconsideration of the dial I58 in Fig. 14 it is seen that the cycle of operations includes a washing operation, two rinsing operations, and a drying or water-extracting operation. The cam shaft H1 in the pre-selector unit 92 is operated at a speed of one revolution per hour, which speed is accomplished by knowledge of the Dre-determined rate of speed of the motor 4| and a proper determination of the gears connecting the motor shaft 39 with the cam shaft II 1. By virtue of this speed of operation of the cam shaft II1 it is apparent that the camshaft, and in turn the cams mounted thereon, will be rotated through an angular distance of 6 each minute. The time period required for each operation, in the cycle of washing operations, can thus be indicated directly On the dial I 58.

It is well known, of course, that many of the operations within the cycle of operations to be performed for a desired washing of the clothes inthe receptacle 21' take place concurrently and in an overlapping relation. In order, therefore, that the cams II15dl08d, and III5eII)8e, properly provide for the proper occurrence of the various operations, a time cycle of these operations may be indicated on a chart I59 shown in Fig. 11.

In the chart I59 each square I6I longitudinally of the chart designates a minute, so that the chart in effect is a developed view of a cylindrical time chart contemplated to be rotated through one revolution per hour. The various operations to be performed, and corresponding to the operations designated on the dial I58, are indicated in vertical columns, varying in width according to their time periods of operation, with the operations being listed vertically adjacent the lefthand end of the chart. The horizontal heavy lines I 92 indicate the length of time for each operation and the relation of one operation with respect to the remaining operations in the cycle of washing operations.

From the chart 159 the angular length of the high spot or operating portion of the cams IIl'5d- I'EIBd, and I05e-I98e, both inclusive, can be computed directly in degrees by merely determining the minutes required for an operation and multiplying this number of minutes by 6. Thus for example referring to the chart, it will be noted that the drain valve 63 is opened three separate times during the complete cycle of Operations. The cams Ie! and H152 operatively associated with the drain valve 63 are formed with three high spots angularly spaced, with the high spots on the cam I05d having angular lengths computed from the chart Hi9, and the high spots on the cam i056 having angular lengths adapted to overlap the actuating periods of the cam I050! in the manner above explained.

In the operation of the system assume the pointer I43 to be at the oil position indicated on the dial I58 in Fig. 2. The control knob I42 is manually gripped and axially extended to disengage the serrated collar member I39 from the hub of gear I38 and rotated in a clockwise direction, as viewed in Fig. 2, until the pointer I43 is at the beginning of the fill operation, indicated as F on the dial I58, for the washingoperation. This rotation of the knob I42 in turn rotates the cam shaft H7 and the cam I48 to operate the switch I45 for the motor 4|. Thus on release of the manual knob I42, the serrated members I39 and I38 are automatically, engaged and the system conditioned to automatically provide for the performance of all the operations within the cycle of operations indicated on the dial I58, and with the washing operation taking place for the maximum length of time of twenty minutes indicated on the dial I58.

Where a washing period of less than twenty minutes is wanted the knob I42, on completion of the washing fill operation, is lifted upwardly androtated in a clockwise direction to a desired minute mark on the dial I58. It is apparent, of course, that a washing period of less than twenty minutes may be obtained by a single actuation of the knob M2 by the provision of additional high spots on the fill cams I05d and I05e at positions corresponding to the five minute markings on the dial I58 for washing period.

Since the operation of each valve I05a-IOBa, inclusive, in the control head 93 and its control of a corresponding bellows unit is similar in all respects only the operation of the valve I080, will be fully described.

With reference to Fig. 1 it is seen that the valve I580. is operatively associated throughthe conduit I98 with the bellows unit 89 which actuates the clutch device 42 to control the oscillatory movement of the clothes receptacle 2|; and through conduits E59 and I08 with the bellows 16 for actuating the clutch device 56, which connects the pump shaft 60a with the motor shaft 39.

From a consideration of Fig. 11 it is seen that the receptacle 2| is oscillated and the pump 54 operated during the initial filling of the tub 20 and the later following and successive washing and two rinsing operations. The filling of the tub 20 is controlled by the high spots I50 and I M on the cams M511 and I05e, respectively, to supply a fiuid pressure through the conduit I05 to the bellows 6'! of the tub inlet valve 60 or a period of three minutes corresponding to a rotation of the cam shaft I I! through 18.

It is apparent, of course, that the rate at which the tub 25 is filled depends upon the pressure of the water in the city main, but a time period of three minutes is generally, sufficient to fill the tub to its level indicated at.2'|0 in Fig. 1 at a usual city main pressure of about twenty pounds per square inch. However, in,v order to limit the water to the level 2 I 5 at pressures in excess of the usual twenty. pound per square inch pressure there is provided a float valve including a float 2|6 located ina housing 2 I! carried on the outside of the tub 2 3 substantially at the level 2I5. The housing is'fiuid connected with the tub 20 through an aperture 22| in the tub wall at the level 2|5. Suspended from the bottom of the float 2|6 is a valve member 2|8'adapted to seat in a valve seat member 219 threaded in the bottom of the housing 2 I 7 and acting as a guide for the valve member 2I8. A bleeder conduit 220 is connected at one end to the conduit I05 and at its opposite end to the valve seat member 2 I 9.

When the water in the tub 20 reaches the level at 2I5 the float 2IB lifts the valve member 2|8 away from its seat in the member 2|5 whereby water from the conduit I05 is bled to the conduit 220 and into the tub 20 through the housing 2H and opening 22I. This bleeding of water from the conduit I05 reduces the water pressure acting on the bellows 67 of the inlet valve 60, whereby the bellows 57 is permitted to contract to in turn provide for a seating of the valve II on the seat lie to close the inlet valve 60. It is seen, therefore, that the fioat valve acts as a pilot control for the inlet valve 60 to close the valve I50 even though the valve IBM is actuated by the cams E0501 and I05e to supply water in the conduit I05; On completion of the three minute interval for the initial tub fill the valve |05a will be actuated: by the cams I05d and I05e to close the supply' of water to the conduit I05 and in turn the further bleeding of water through the conduit 220 into the tub 20.

The oscillation of the receptacle 2| and operation of the pump 54 during the initial tub fill, the washing and two rinsing operations is accomplished by virtue of the fact that the disc members 12b and 73b, of the clutch 42, and disc members i2 and I3 of'the clutch 56'are normally held in frictional engagement by the action of the springs 81 and I4, respectively. During the initial tub fill, and later washing and two rinsing operations, therefore, the low spots on the cams |08d and I08e, as shown in Fig. 10, are rotated past the ends ||6 of the rocker arms I082) and I 080, respectively. The valve I08a is thus maintained in its normal rest. position shown in Fig. 5 during the time the initial tub fill, washing and two rinsing operations are taking place, so that no fluid pressure is admitted into, the conduits I08 and I09.

On completion of the second rinsing operation the high spots I59 and IBI of the cams |08d and I08e, respectively engage the ends N6 of the rocker arms I08b and I080, respectively, to operate the valve I08a to its position shown in Fig. 9. Water is thus supplied into the conduits I08 and I09 for application on the bellows 89 and I6.

The water admitted into the conduit I08 expands the free end of the bellows 89 to the right, as viewed in Fig. 1, to pivot the lever arm 19b in a counter-clockwise direction, as also viewed in Fig. 1, tom turn move the disc member 131), against the pressure of the spring 81, out of frictional engagement with the disc member 122). The opening of the clutch device 42 takes place substantially concurrently with the closing of the clutch device 32 by the valve unit I 01a so that the receptacle 2| is substantially. immediately rotated to perform a drying operation as indicated in the chart I59 (Fig. 11). Since the conduit I09 is connected with the conduit I08 it is apparent that the bellows IE will be operated concurrently with the bellows 89 to operate the clutch device 56 and stop the operation of the pump 54.

The clutch devices 42 and 56 are held open, during the drying operation, by the bellows 89 and I6, respectively, for a period of time corresponding substantially to the angular length of the high spot 15.9 on the cam I 08d. When the cam high spot I59 passes out of an engaging position with the end .II6 of the rocker arm I08b the pressure header 94is closed from communication with the conduit I08. On disengagement of the end N6 of the rocker arm I 080 with the high spot I6I of the cam "186 the conduits I08 and I09 are opened to the waste header 96 whereby to release the pressure in the conduits I08 and I09. By virtue of this pressure release in the conduits I08 and I09 the bellows I6 and 89 are contracted by the action of the springs 14 and 81, respectively, whereby to provide for a concurrent closing of the clutch devices 56 and 42, respectively.

It. is. believed that the operation of the remaining bellows by their corresponding valves in the control head 92 will be apparent from the above detailed description of the valve unit I08a, so that a detail description of their operation is believed to be unnecessary.

With reference to the chart I59 in Fig. 11, it is seen that the tub outlet or drain valve 63 is held open three'different times during a complete cycle of operations, 1. e., to empty the tub 20 following the washing operation and each of the two rinsing operations. The operation of the valve 63 in this manner is accomplished by the provision of three angularly spaced high spots, on the cams WM and I062 (Fig. 1 in a relation providing fora desired actuation of the valve l06a to properly control the application and discontinuance of a fluid pressure on the bellows 61 of the valve 63. It is to be understood, of course, that the control action of the float 2I6 will have precedence over the control action ofthe cams I06d-I06e for all tub filling operations. i

Similarly the cams IBM and Ie are each formed with three angularly spaced high spots toprovide fora predetermined opening of the inlet valve 60 preceding the washing operation, andthe two rinsing operations. It will be noted in Fig. 11 that the fill operation before each rinse is in an overlapping relation with a preceding drain operation. This is for the purpose of flushing the tub 20 before it is filled with clean water.

The spinning operation is controlled by the actuation of the valve I0Ia by the cams I0Id and I0Ie so that pressure is applied on the bellows 8 4 for the clutch device 32 during the drying operation when the clutch devices 42 and 56 are in their open positions. It will be noted that the drainvalve 63 is retained open during the drying operation so that all moisture removed from the clothes by spinning the perforated receptacle 2| isimmediately drained from the tub Z0.

On completion of the drying operation all of the valves l05a-I08a, inclusive are returned to their normal rest positions, as shown for the valve l08a in Fig. 5, so as to close all of the conduits I05-I08, inclusive, from communication with the pressure header 94. Following the return of the valves I05c--I08a to their normal positions the high spot I53 on the cam I48 for the switch device I45 aotuates the lever arm I46 to openthe contacts I54 and I56 to stop the opera tion of the motor 4|. The complete cycle of washingoperations is thus automatic and may be repeated by initially manually actuating the knob. I 42 in the manner above explained;

It is seen, therefore, that the motor 4I isutilized in the control system only as a timing means for driving the preselector unit 92. By virtue of the slow rate of operation of the cam shaft II! the power taken for this purpose from the motor M is very small and in the neighborhood of one foot pound per hour. A11. of the power for operating the inlet valve 60, drain valve 63, and clutch devices 32, 42 and 56 isprovided by the pressure of thefluid admitted to the pressure header 94. Although the source of fluid supplied to the chamber 94 has been described as coming from a usual city water main,.it:is to be understood that it may be supplied by any other suitable means such as an independent pumping system or the like. It is apparent, also, that the system will operate efficiently whether thefiuid admitted to the header 94 is water, air, or a combination of the two, and that it may also be operated with a suction pressure in the pressure header 94 by a slight modification in the lever system connecting the bellows units 89, 86 and 16 with their corresponding clutch devices 42, 32 and 56, and by reversing the action of the bellows 61 relative to the valve member I If, in the tubvalves 60 and 63.

The. system has been found to operate efiiciently and satisfactorily over a pressure range in the header 94 of between five and thirty-five pounds per square inch whereby it can be used in localities or cities having different pressures in their water mains. Whenpressures of five pounds per square inch are used the various bellows may be increased in size, relative to their size for higher pressures in the neighborhood of about twenty pounds per squareinch, so as to efletctively actuate their corresponding operating um s. i

The provision of a pressure-actuated control system for a washing machine or the like also provides for a smoother starting of the operating units in the machine. Thus for example with reference to the operation of the clutch device 42 by the control valve I08a it is apparent that a lag will occur between the operation of the valve I08a and the operation of the clutch device 42 to either stop or start the oscillatory movement of the clothes receptacle 2|. This lag period occurs by virtueof the time required for the fluid pressure in the chamber 94 to build up within the conduit I08 and the bellows unit 09. Also this pressure build-up is gradual so that the frictional engagement between the disc members 12b and 13b takes place progressively to a maximum frictional engagement as determined by the pressure within the header 94. Due to the frictional engagement between the disc members 1217 and 13b taking place gradually slippage may occur betweenthe disc members so that any sudden overloading of the motor 4| is entirely eliminated, as is alsoany sudden changes in the move ment of the receptacle 2I from an oscillatory to a spinning operation, and from a standstill to an oscillating operation. It is further apparent that not only is the application of the pressure from the header 94 gradually applied on the bellows, but the maximum pressure to be applied can be regulated by merely varying the desired maximum pressure in the header 94 through the pressure regulating valve I00a. As a result both the. maximum fluid pressure, and its rate of application on the bellows and in turn on the actuating. units in the machine can be varied over relatively wide. limits, dependent upon any desired condition of operation, by controlling the valve IOI in conjunction with the pressure regudue to the time lag which takes place in the building up of a pressure in a conduit I05I68 equal to the pressure in the header 94 on actuation of a control valve IIl5a-IIl8a. Thus assurne that the first rinse operation is to be eliminated. On completion of the washing operation the knob I42 (Fig. 2) is manually raised and the pointer E43 rotated from a position at A to a position at B covering an angular distance normally required for the first rinsing operation. The manual rotation of the pointer I43 and in turn of the shaft H1 is at a relatively fast rate, compared to the normal rotation of the shaft at one revolution per hour, so that the cams I650! and I056, and 10601 and W642, for the valves "d and WM, respectively, which control the valves 66 and 63, respectively, pass into and out of engagement with the rocker arms in these valves at a speed such that the pressure head 94 is in communication with the conduits I05 and I86 for a time insufficient to permit a pressure build-up in these conduits capable of actuating the bellows 61 in the valves 60 and 63, respectively. As a result the valves 60 and 63 are not operated on manual rotation of the pointer to skip the first rinsing operation. In like manner any one or more operations can be omitted from the cycle without any actuation of the operating units, which would be actuated in a normal running of the cycle.

As shown in Fig. 1 the control head is in an upright position with the drain pipe I23 for the waste header 96 at its bottom. Also all of the conduits [95469, inclusive, are located substantially below the level of their corresponding bellows and stepped down to the waste header 96. When the system is at rest, therefore, all of the fluid therein is drained by gravity flow into the waste header and out of the system through the drain pipe I23.

The control head 93, as described above, provides for the performance of a plurality of operations in a predetermined cycle, and with all of the operations taking place within at least a one hour period. Referring to the dial I58 in Figs. 2 and 14 it is seen that the washing operation is variable between a time period of from zero to twenty minutes, with the twenty minute time period corresponding to a rotation of the pointer I43 and in turn of the cam shaft II1 through an angular distance of 120. It is, of course, well known that the length of the washing period varies for different kinds of clothes and for badly soiled clothes as compared to slightly soiled clothes.

Referring to Figs. 14 through 17, inclusive, there is shown a modified form of control head which provides for the extension of the washing operation for longer time periods than twenty minutes, and within the 120 angular travel of the cam shaft I I1 normally required for a twenty minute Washing operation. Since the modified 16 control head is similar in most respects to the control head 93 in Fig. 1 similar numerals of reference will be used todesignate like parts.

A set of worm gears I21 and I28, and gears 136-4 38, cam shaft I I1, manual knob I42, pointer Hi3 and dial I58 are operatively assembled with a gear casing I62 in a manner similar to the assembly of the like parts with the gear casing I26 as described in connection with Fig. 1. The flexible shaft I25 carries a bevel gear I63 which is in meshing engagement with a bevel gear I64 mounted on a shaft I66 rotatably supported in the gear casing side wall I61 and in a bearing member E68 projected inwardly from the gear casing side wall I69 (Fig. 15). Rotatable with the shaft I66, and axially movable thereon, is a friction gear I'II having a hub portion I12. The periphery of the friction gear I1I is frictionally engageable with the side face of a friction gear I13 mounted on a shaft I14 which also carries the worm I28. The gears HI and I13 are retained in frictional engagement by a coil spring I16 mounted about the shaft I14 and arranged in compression between the gear I13 and a frame member I11 in the gear housing I62.

Movement of the gear I1I axially of the shaft I66 to a changed position relative to the face of the gear I13 is accomplished by means including a bell crank I18 pivoted at I19 on the frame member I11. The free end of the bell crank arm I8I is pivoted to a yoke member I82 which rides freely in an annular groove formed in the hub I12 of the friction gear I1I. The free end of the arm I83, of the bell crank I18, is pivoted at I84 to a second bell crank I86. A tension spring I81 is connected at one end to the arm I88 of the bell crank I86 and at its opposite end to the side wall I69 of the gear casing I62, for a purpose which will be later explained.

The free end of the arm I89 of the bell crank I66 is formed with a pawl portion I9I and a projection I92 which are extended in opposite directions laterally of the arm I69 (Figs. 15, 16 and 17 The pawl I6I is operatively associated with a ratchet bar I93 carried on the inner surface of the gear housing side wall I94. An upright finger grip I96 is positioned on the arm I89 substantially between the pawl I9I and the projection I92 and extends through a slot I91 in the gear housing side wall I94 which is in a parallel relation with the ratchet bar I93. A pointer I98 extended laterally from the finger grip I96 is associated with a linear dial I99 carried on the outside surface of the side wall I94 in a parallel relationwith the slot I91. The dial is graduated in minute markings ranging from twenty to fifty.

An elongated bar 20I, parallel with the slot I91, is pivoted at its ends 202 and 203 to the inside of the gear housing side wall I94 (Figs. 14 and 16). The bar 26I is supported against downward movement by the projection I92, so that the projection I92 is slidably movable on the under side of the bar 20I as shown in Figs. 16 and 17. Adjacent the end 263 of the bar 29I is an upright projection 264 which is extended through an opening in the gear housing side wall I94 and dial I58 for engagement with the pointer I43.

In the operation of the control head in Figs. 14 through 16,. let it be assumed that a Washing period between zero and twenty minutes is desired. The finger grip I96 is moved against the end 296 of the slot I91, to in turn move the crank arms I86 and I18 to adjust the friction gear I1I relative to the friction gear I13, to one operating position which shall be termed the 17 normal position and provides for "aspeed of rotation of the cam shaft I I1 of one revolution per hour. This normal position shown in Fig. 15, is retained by the action of the spring I81 which holds the finger grip I96 against the slot end 206. With thefinger grip I96 in stop engagement against the slot end 296 a, washing period of anywhere from zero to twenty minutes is accomplished by adjusting the pointer I 93 relative to the dialIEB in the manner above explained in connection with the control head 93 in Fig. 1.

Now assume that a washing period of longer than twenty minutes is desired, such for example a washing period of fortyminutes. This washing period is obtained by, moving the finger grip I96 until the pointer I98 is at the forty minute marking on the linear dial I89. This movement of the finger grip I96 moves theibell crank I86 to the left as viewed in Fig. to a position corresponding to theforty minute washing period, which position is retained by the pawl I9I engaging the ratchet bar I93. The movement to the left of the bell crank I 89 in turn rotates the bell crank I18 in a counter-clockwise direction, and the yoke I82 upwardly, as also viewed in ,Fig. 15, whereby the friction gear I1I is moved upwardly, from its normal position shown in Fig. 15,toward the periphery of the friction gear I13. This movement of the friction gear I1I relative to. the friction gearI13 reduces the speed of rotation of the friction gear I13 in a manner which is'believed to be apparent. By a proper determination of the relative sizes of the friction gears HI and I13 relative to the minute markings on the dial I99, a speed of rotation of the cam shaft H1 is provided at which forty minutes will be required to rotate the cam shaft II1 through the 129, or twenty minute period, allotted to the washing operation on the dial I58.

Near completion of the washing operation the pointer I43 engages and depresses the upright projection 294 on the bar 29I to in turn pivot the bar 29I in a clockwise direction, as viewed in Fig. 16, to depress the projection 294 and move the pawl I9I out of engagement with the ratchet bar I93. With the pawl I9 I disengaged from the ratchet I93 the projection I92 is slidably moved relative to the bar 29 I by the action of the spring I81, until the finger grip I96 is returned to its position against the end 296 of the slot I91. :Concurrently with the movement of the finger I96 against the slot end 296 the friction gear IN is moved downwardly to its normal position shown in Fig. 15. The gears, on completion of the washing operation, thus provide for a rotation of one revolution per hour for the remainder of the operations to be performed in the cycle.

It is to be understood, of course, that the minute indications on the dial I99 are supplementary to the minute indications on the dial I58 so that the pointer I43 is always set at the zero marking on the dial I58 after the pointer I98 has been set to a minute marking on the dial I99 greater than twenty minutes. As a result of the adjustment of the friction gears HI and I13 a wide variation in the time period required for a washing operation can be accomplished within a predetermined angular rotation of the cam shaft I I1.

With reference to Figs. 12 and 13 there is shown a modified form of rocker arm 2 I9 adapted to be used in the valves I95w-I08a, inclusive, in place of the rocker arms 19517-4981) and I95c- 18 I08c,--shown. in Fig. 1. When therocker arm 2I9 is used-the cams Idl98d are eliminated and only the cams I95eI98e are employed. For the purpose of clarity of description the rocker arm 2E9 in Figs. .12 and 13 will be described relative to its substitution for the, rocker arms I98!) and i980 in the valve I98 a, so like numerals of reference, therefore, will be used for corresponding partsin Figs. 5, .8 and 9. i

The rocker arm 2I9 is of a substantially triangular shape having a hub 299 at its central portion for mounting on the rocker shaft H3. The three apexes of the rocker arm are provided with arcuate shaped portions 2| I, 2I2 and 2 I3 for engaging the cam I98e, the tube I94 adjacent a pressure header outlet I92, and the tube I94 adjacent a waste header inlet I93, respectively. A spring I I9 connected at one end to the bracket Iii and at its other end adjacent the portion 2| I holds the rocker arm 2m in a normal rest position, shown in Fig. 12, at which the portion 2I2 pinches the tube I94 closed adjacent the outlet 192, while the portion 2 I3 is out of a tube-closing position.

iWith the, rocker arm 2I9 in its normal position the conduit. I98is closed from the outlet I92 and open to the inlet I93 for the wasteheader 96.

On rotation of the cam shaft I I1 in a counterclockwise direction, as viewed in Fig. 12, the high spot 161 on the cam I99e engages the portion 2| I and rocks the arm 2I9 in a clockwise direction, as also viewed in Fig. 12, to move the portion 2i2 out of a tubeepinching position and the portion 2I3into a tube-pinching position. The conduit I99 is thus opened to the pressure header 93 and closed from the waste header 96.

It is apparent that during the movement of the portion 2! I from the lowspot of the cam I98e to its high spot I6I both of the portions 2I2 and 2l3 will be concurrently out of tube pinching positions. As a result the pressure header outlet 592 will be open to both the conduit I98 and the waste header inlet I93. However, since the time interval required for the movement of the portion 2H to atop position on the cam high spot i9l is relatively short, very little water will be wasted by virtue of the tube I94 being open over its entire length by the concurrent actuation of the portions 2I2and2l3 by the cam I98 e. From adconsideration of the above description it is seenthattheinvention provides a hydraulic control system operated from the available water pressure in ,a, city main and capable of automatically controlling a washing machine or the like to perform a predetermined cycle of operations. The system is flexible in application to actuate any number of operating units in the machine and provides for the performance of a series of operations within the cycle of operations, without producing the performance of the remaining operations in the cycle, and capable of varying the time period of an operation over relatively wide limits. Further the system may be operated with pressures ranging from a low pressure in the neighborhood of five pounds per square inch to a high pressure of about thirtyfive pounds per square inch by merely changing the bellows 61, I6, 84 and 89 to a desired cross sectional area commensurate with the available pressure to effectively actuate their corresponding operating units.

Although the invention has been described with respect to several preferred embodiments thereof it is to be understood that it is not to be so limited since changes can be made therein 

